Apple Tree Diseases

September 19, 2015

We moved to a new home about a year ago and it had an apple tree in the yard.

This spring it bloomed and small apples began to grow. After the apples were about
walnut size I noticed a few brown spots on some of them. After about a week half the
apple appeared rotten. Eventually all the apples did the same. I don't know what kind
of apple tree this is, or how old it is. It's around 20 feet high. Do you know why
this happened? Should I have sprayed it with something?

Apples and pears tend to be more forgiving than peaches and plums when it comes to
insect and disease issues, but if you want blemish free large fruits, you need to
follow a spray schedule. There are numerous diseases and insects which can attack.
Here is a link to our home fruit spray schedule: http://www.uaex.edu/publications/pdf/FSA-7503.pdf . They also need to be pruned annually as well.

(April 2010)

I am having difficulty with my fruit trees. Last year my peach tree produced lots
of peaches, but they all dried up around the seed before they ripened. I also noticed
that quite a few of the leaves and small branches dried up and died. My apple tree
made really good apples but the leaves dried up and died and I noticed yellow spots
on the leaves that had several round dots in them. I assumed these to be some kind
of insect eggs. The apples also had dark spots on them. I have already cut them back
and am hoping that you can suggest some kind of spray, preferably something natural
that I can use to solve these problems

Fruit trees can be challenging for the home gardener, especially peaches which have
numerous insect and disease issues. Brown rot is the most destructive and can wipe
out a crop seemingly overnight, especially when we have periods of rain, which were
almost constant last year. Pruning is something you will need to do annually, but
a spray schedule is also necessary to produce quality fruit. Purchase a home fruit
spray which has both an insecticide and a fungicide mixed together. There are organic
products as well as non-organic. Start spraying when two thirds of the flower petals
have fallen and then continue throughout the growing season, about every 10 days to
three weeks depending on the weather. Your apple tree sounds like it was infested
with cedar apple rust. This disease has two hosts--Eastern red cedars and apple trees.
By the time you see yellow spots rimmed in orange it is too late to spray to control
it. The key is to do preventative sprays the first few weeks following bloom. Orange
gelatinous masses form on cedar trees releasing spores which then infest the apples.
Typically apple diseases are a bit easier to deal with since you can usually peel
off the damage and still eat the fruit. Spray schedules, cultural information and
pruning guides are available on our Extension website at: http://www.arhomeandgarden.org/

(May 2010)

I live in northwest Arkansas and we have some small cedar trees at the edge of our
lawn that has some orange (fungus?) looking things growing out of grey nuts? They
look like a bunch of tentacles and are mushy. Are these harmful to the cedars?

What you are seeing with the bright orange tentacles is the fruiting body of cedar/apple
rust on your cedar tree. This disease has two hosts--Eastern Red Cedar and apples/crabapples.
The disease first starts on the cedar. During periods of rain in the spring the galls
quickly grow orange, gelatinous tentacles that produce spores which then blow to
the developing fruit and leaves on nearby apple and crabapples trees. Symptoms will
appear on apple foliage as small round orange spots which then yellow. Heavy infestations
can cause the apple trees to shed foliage and deform the fruit lightly, but the disease
is not deadly to either plant. If you desire clean fruit, fruit sprays are needed
in early spring. They are only effective during the time the spores are active in
early spring, and once you see symptoms, sprays are no longer effective. If you don’t
grow apple trees, you can ignore them or simply enjoy their odd appearance. Here
is a link to a fact sheet for more information: http://www.uaex.edu/publications/PDF/FSA-7538.pdf

(June 2006)

We planted a few young apple trees last year. They leafed out well, even had a few
flowers and now small fruit--they have been growing great, but a few weeks ago I noticed
some of the leaves looked black and wilty. I at first thought it was just because
it was because they were still young but it doesn’t seem to be outgrowing it. Can
you tell me what is wrong by this sample? What can I do to save the tree?

The plant sample you sent has fireblight--a bacterial disease. Generally succulent,
rapidly growing twigs and shoots are most susceptible. There is no sprayable cure,
but the disease pressure should stop now that hot weather is here. This has been an
extremely prolific fireblight year. Just cut out the damage 6-8 inches beneath where
it is visible. Sterilize your pruning shears after each cut with rubbing alcohol or
a Clorox solution. Be sure to clean and oil your shears when you are done pruning.

All links to external sites open in a new window. You may return to the University
of Arkansas Division of Agriculture web site by closing this window when you are finished.
We do not guarantee the accuracy of the information, or the accessibility for people
with disabilities listed at any external site.

Links to commercial sites are provided for information and convenience only. Inclusion
of sites does not imply University of Arkansas Division of Agriculture's approval
of their product or service to the exclusion of others that may be similar, nor does
it guarantee or warrant the standard of the products or service offered.

The mention of any commercial product in this web site does not imply its endorsement
by the University of Arkansas Division of Agriculture over other products not named,
nor does the omission imply that they are not satisfactory.